1. Field of the Invention
The present invention relates to a steam generator, and, more particularly, to a steam generator capable of preventing impurities, such as water droplets, air bubbles, etc., from entering a steam ejection hole, and a heating cooking apparatus having the steam generator.
2. Description of the Related Art
Examples of heating cooking apparatuses used to cook food include a microwave oven using high frequency microwaves, and an oven using a heater. The microwave oven can only cook limited types of food, although the food is cooked within a relatively short time. The microwave oven also suffers from deterioration in the quality of cooked food because of excessive drying of the food. On the other hand, although the oven using a heater guarantees better quality of food because the food is cooked in an optimized closed space, the oven has problems of excessively long cooking time and low cooking efficiency because low density air acts as a heat transfer medium between the heater and food.
Recently, to compensate for the above described problems of the heating cooking apparatuses, heating cooking apparatuses for supplying heat to food via steam (vapor) have been developed. One example of this type of heating cooking apparatus is disclosed in Japanese Patent Laid-open No. 2004-0162936. The disclosed conventional heating cooking apparatus includes a steam generator for generating steam.
Conventionally, a steam generator includes a tank for storing water therein and a heater for heating the water. After heating and evaporating the water stored in the tank, the steam generator supplies the resulting vapor into a cooking compartment.
However, in the conventional heating cooking apparatus using the above described steam generator, there are problems in that air bubbles, which are generated in the course of boiling water by use of a heater and which grow to an excessively large size, or water droplets, which are generated as the air bubbles burst, are introduced into a steam ejection hole of the steam generator, thus preventing the generation of steam. Another problem is that scale may be accumulated around the steam ejection hole due to the use of tap water, thus causing the steam ejection hole to be clogged or narrowed.